Radio Frequency Sensing based on Rydberg-Atom Electrometry

Rydberg atom-based sensors are used to detect radio frequency (RF) electric fields. These sensors have useful properties such as self-calibration, broad carrier bandwidth and high transparency to RF electromagnetic fields. In a room temperature vapor cell filled with cesium atoms, both 2-photon and 3-photon excitation and readout schemes have been demonstrated. In this poster, several different technical advances that move Rydberg atom-based sensors towards real applications are described. First, we show a co-linear 3-photon scheme that minimizes the wavevector mismatch and thereby reaches sub-200 kHz linewidths at room temperature. We demonstrate the benefits of a narrow linewidth 3-photon setup in extending the self-calibrated regime to weaker RF field amplitudes, while obtaining high sensitivity to RF pulses. Second, we describe a laser system which can switch between wavelengths, spanning around 8 nm, in a few hundred microseconds. This narrow-linewidth, frequency stabilized laser solves the problem of rapidly changing the RF frequency that is detected. Finally, we present results on engineered vapor cells that can act as amplifiers for the RF electromagnetic field, enhancing the interactions between the RF field and atom.